Reading is a very important component in the teaching and testing of the English language in Hong Kong secondary schools. Using a multiple choice reading comprehension test, this study aims to investigate the possibility of asking secondary English teachers to match test items with particular reading subskills, to examine the existence of 'higher' order and 'lower' order reading subskills, and to diagnose the mastery of reading subskills of a particular group of subjects. 183 Form 5 students were selected as subjects in the study. They were asked to read an expository text and to answer 14 multiple choice test items and to judge the degree of difficulty of the items. Their responses were gathered and analyzed. Another facet of the study involves the judgement of 6 secondary English teachers on the mapping between the 14 test items with 7 reading subskills and on the degree of difficulty of both the test items and the reading subskills. The results of the study show that the judges are able to match most of the test items with the reading subskills, that there appears to be a lack of clear distinction between 'higher' order and 'lower' order reading subskills, and that it is possible for such a test to diagnose the mastery of reading subskills of a particular group of subjects, with more proficient ones possessing far more reading subskills than less proficient ones. The implications of these results for both teaching and further research are also put forward.